Web spreading device



J. 'rHlEL ETI.

Ruda/f Beyer Mn. g

Oct. 30, 1962 WEB SPREADING DEVICE Flled July 22, 1960 I) lb .1.11.111-

MHIIIIII u 1 3,060,545 WEB SPREADHN G DEVICE Johann Thiel, Viersen, and Rudolf Beyer, St. Tunis, near Krefeld, Germany, assignors to E. F. Kress Sohne, St. Tunis, near Krefeld, Germany Filed July 22, 196i), Ser. No. 44,604 6 Claims. (Cl. 26-63) The invention relates to improvements in devices for spreading continuous webs of fabric, paper, film and like goods. It is common practice to spread out a web as uniformly as possible from its centerline towards its two lateral edges, that is, to exert suitable tensile forces, acting in transverse direction, upon the web. This purpose has been successfully served by devices wherein the web is passed over the periphery of a cylinder comprising a plurality of elastic laces. One such device is described in applicants German Patent No. 944,939. The elastic laces are set, axially extensible and secured against slipping out, into longitudinal grooves on a cylinder. The wobblers each consist of an inner hub longitudinally adjustably mounted on the shaft of the cylinder while being pivotable about a transverse axis, and an outer ring free to revolve on the inner hub, the elastic laces being attached to this ring. Usually a single, continuous elastic lace is ernployed, passed alternately from right to left and back again over fittings such as pulleys, rollers, guide pins or the like, mounted on the periphery of the said outer rings. When the device is not in use, the two wobblers may be brought into a neutral position perpendicular to the cylinder shaft and, by suitable axial displacement, moved close enough to each other so as completely to relieve the elastic laces stretched between them. Before the device is put into service, the wobblers are run apart on the cylinder shaft towards its ends until the laces are sufficiently taut, and then pivoted together with their inner hubs about their aforementioned transverse axes into an operative position oblique to the cylinder shaft. When the afore- Vmentioned cylinder is set in rotation by passage of a web of material over it, the bundle of elastic laces set into the longitudinal grooves on the cylinder and hence also the outer rings of the two wobblers are also rotated. As the outer rings revolve on the inner hubs, inclined contrary to each other and set obliquely to the cylinder shaft, the elastic laces stretched between the wobblers will during each revolution of the outer rings, be elongated in the longitudinal direction of the cylinder shaft, and relaxed again in the second half of each revolution, between the two diametrally opposite points on the outer rings where the distance between the rings is respectively greatest and least. If the web is laid upon the cylinder at or just beyond the point where the elongation of the elastic laces begins, and taken oft again at or just short of the point where the maximum of elastic elongation is reached, then the web material will be subjected to uniform traction from its lengthwise midline towards its two lateral edges by the elastic elongation of the laces and thus spread out smooth.

The present invention proposes to improve the devices for spreading continuous webs as described above, and particularly the device described in applicants German Patent No. 944,939, in a number of respects. One chief object of the invention is to prolong the life of such a device, in particular that of the elastic laces, which are principally exposed to wear. Secondly, the device is to be fully adapted to wet operation. This requires protection of all its bearings against penetration of moisture, dust and foreign particles generally, especially the bearings of the hollow cylinder on its shaft and Vthose of the outer rings of the two wobblers on their inner hubs.

Another object of the invention is t provide eflicient analisis Patented Oct. 30, 1962 ice means, of simple construction and convenient operation, for adjusting and setting the two wobblers on the shaft supporting them.

The device according to the invention will now be more fully described with reference to the accompanying drawing, but it should be understood that such description is given merely by way of illustration and not of limitation and that many changes in the details may be made without departing from the spirit of the invention.

In the drawing:

FIG. 1 shows a view, partly in section, of the pertinent parts of an embodiment of the invention;

FIG. 2 shows a cross-section, drawn to a larger scale, on the line II-II in FIG. 1;

FIG. 3 shows a cross section on the line III-III in FIG. l; and

FIG. 4 shows a detail of FIG. l, in a somewhat different position.

A shaft 10, mounted in conventional manner on a framework (not shown), is fitted with ball bearings 11 on which a hollow cylinder 12 rotates. The periphery 12a of cylinder 12 is provided with undercut longitudinal grooves 13, as may be seen in FIG. 2. Into each groove 13, an elastic lace 14 is set, with a little clearance, so that although the lace is able elastically to elongate and contract within the corresponding groove 13 in longitudinal direction, it is secured against slipping out of the groove when the hollow cylinder 12 is rotated. The elastic laces 14, made of suitable synthetic material, are united into one continuous strand, laced alternately from left to right and back again over the periphery 12a of the cylinder. At each point of reversal 14a (FIGS. 1 and 3) of the continuous elastic lace, there is a pin 15 about which the lace is passed. Like the longitudinal grooves 13, the pins 15 are evenly spaced on the circumference of a cylinder: the grooves 13 on the periphery of the hollow cylinder 12, and the pins 15 on the periphery of rings 16 at each end of cylinder 12. Each of the two rings 16 (FIG. 1) is freely rotatable by means of a ball bearing 17 on a hub 18, fixed in turn on shaft 10, The hub 18 and ring 16 together form a system 20 acting as a wobbler.

The hub 1S of each wobbler 20 has a central opening 23 of oblong cross-section. Its sides engage ats on shaft 10, so that the hub will not rotate on the shaft but may be shifted longitudinally on shaft 10 and also pivoted about a transverse axis. The transverse pivot for hub 18 is a pin 24 guided by a lengthwise slot 25 in shaft 10. System 20 is made to function as a wobbler by suitable rotation of hub 18 on transverse pin 24. As is best seen in FIG. 3, the hub 18 of each wobbler 20` is mounted on its transverse pin 24 with an eccentricity of a few millimeters. In the position of shaft 10 and the left wobbler 20 as shown in FIG. l at the left and in FIG. 3, the points of reversal of the elastic lacing on the corresponding outer ring 16 are displaced upward relatively to the hollow cylinder by the amount of the said eccentricity.

On each side of the ball bearing 17 of each wobbler 20, the hub 18 contains a packing ring 19. Packing rings 19 prevent moisture, dust, lint and other foreign matter from entering the assembly of ball bearing 17 with outer ring 16 and hub 18 of each wobbler 20. The points of attachment of the elastic laces 14, or the points of reversalr14a on wobblers 20, may also be protected from moisture and foreign matter by a guard 21 secured to and partly over lying the ring 16 as shown in the left-hand half of FIG.l 1, or else the hub 18 may be extended to clear the ring 16 and form a guard enclosing the outer ring 16 and points of reversal 14a from without. Outside each ball bearing 11 between hollow cylinder 12 and shaft 10 is fitted a packing ring 22 to prevent penetration of moisture and foreign matter into this bearing from the outside.

The pivot 24 of each wobbler Ztl is xed to the inward end of a spindle 26 (FIG. 4). The spindle 26 travels in an axial recess 27 of the corresponding end 10a of shaft 10. At each shaft end 19a, a nut 28 with hand lever 29 and knob 30 is rotatably but not slidably mounted. Each nut 23 has a self-locking trapezoidal internal thread engaged by a matching external thread on the head 26a of spindle 26.

On the hub 18 of each wobbler 2t), there is `an arm 31 projecting outwardly in the longitudinal direction of shaft 1i) and bearing a roller 32. This arm 31 acts as a pawl cooperating with a lug 33 fixedly mounted on shaft 1t) and having an inclined surface 33a.

In the inoperative position of the device described above for spreading continuous webs, the wobblers 20, as shown in FIG. l at the left, are in perpendicular position relative to shaft on which they are thrust inward to their minimum distance from hollow cylinder 12. In this position of wobblers Ztl, the elastic laces 14 stretched between the two are relaxed. Now if one nut 28 is turned in the proper direction with the aid of lever 29, spindle 26 and pin 24, with which the nut forms an adjusting mechanism, will pull the hub 18 of the corresponding wobbler outwardly without at first altering its perpendicular position relative to shaft 10. When the roller 32 of arm 31 begins to mount the inclined surface 33a of the lug 33 seated on shaft 10, the `corresponding hub 18 of wobbler 2t) will rotate by a corresponding amount upon its transverse pivot. Then the corresponding wobbler 2t) assumes the operative position, oblique to shaft 10, shown in FIG. l at the right. In this arrangement, the two wobblers 2t), in operative position, have those halves inclined towards each other that are displaced radially outward by the amount of the aforementioned eccentricity of a few millimeters relatively to the periphery 12a of the hollow cylinder 12.. Those peripheral points of wobblers that, in the convergent operative position of the two wobblers, have the least axial distance from each other are therefore simultaneously at the greatest radial distance from the centerline 34 of shaft 1t). Opposite these two peripheral points, there are two other peripheral points of wobblers 20, having the smallest radial distances from the centerline 34 but the greatest axial distance from each other. The line connecting the former two peripheral points is the upper extreme, and the one connecting the latter two peripheral points of wobblers 2t) is the lower extreme, of the bunch of elastic laces 14. In each revolution of wobblers 20, or their outer rings 16, the elastic laces 14 successively pass in the direction of rotation of cylinder 12 from the aforesaid upper extreme to the lower extreme and back again. Owning to the said eccentricity, those laces 14 which are at any moment located at or near the lower extreme of the bunch, and the most elongated, are drawn radially into the longitudinal grooves 13 because the points of attachment of these laces to wobblers 2() lie at the minimum radial distance from the centerline 34 of shaft 10. Therefore the laces 14, precisely when most elongated and accordingly most constricted in cross-section, and thus most apt to slip out of the corresponding longitudinal grooves 13 on the periphery of cylinder 12, are pulled against the backs of these grooves and thus fully secured against slipping out. Near the top extreme of the bunch, the elastic laces 14 are least elongated in the course of a revolution of wobblers 20, and hence are greatest in cross section. In this vicinity, they therefore till the corresponding longitudinal grooves 13 on the periphery of cylinder 12 completely, and are prevented from slipping out by the undercutting of grooves 13. It has also been found that the few millimeters of eccentricity in mounting wobblers 20 0n shaft 10 of hollow cylinder 12 work out to advantage in another respect, in that the elastic laces 14 suffer considerably less abrasion against the walls of grooves 13 into which they are set, in operation, than when the wobblersl are mounted concentrically. By these means and the aforementioned precautions against the action of moisture, dust and other foreign matter, the service life of the elastic laces and all bearings of the hollow cylinder and wobblers, which are the principal components exposed to wear, is substantially prolonged.

The arrangement described for adjusting and setting the wobblers affords a peculiarly simple `and convenient management of this operation. Also, all parts of this arrangement yare readily accessible and replaceable. Of course, the lugs 33 fixed on shaft 10 may be `axially adjustable and capable of being fixed in place. Then the preliminary tension of elastic laces 14 as a result of axial extension of the two wobblers 20 may be suitably adjusted lbefore rollers 32 of arms 31 climb the inclines of lugs 33 to bring wobblers 20 out of their inoperative position pelpendicular to shaft 10 into their convergent operative positions oblique to that shaft.

What we claim is:

l. In a device for spreading continuous webs of fabric, the combination comprising a shaft; a cylindrical body substantially coaxially journaled on said shaft for rotation relative thereto, said body being formed with a plurality of angularly spaced longitudinally extending grooves along the periphery thereof; respective wobbler means disposed on said shaft at each extremity of said body, said wobbler means each including an annular hub surrounding and pivotally secured to said shaft for limited angular displacement about an `axis transverse to the axis of said shaft and offset therefrom, and an outer annular member journaled for free rotation on said hub; elongated resilient means interconnecting the outer annular members of each of said wobbler means and having portions extending outwardly of the periphery of said body; and control means respectively assigned to each of said wobbler means for angularly pivoting said hubs from an inoperative position of said hubs perpendicular to said shaft into an operative position wherein the `peripheral portions of said hubs remotest from their respective pivotal axes are inclined toward each other.

2. The combination according to claim l wherein at least one of said control means includes a spindle nut provided with a self-locking internal thread rotatably mounted on one end of said shaft adjacent the correspending wobbler means, said shaft having a longitudinal bore and a pair of opposed longitudinal slots communieating with said bore, a spindle having a complementary externally threaded end in engagement with said nut mounted in said longitudinal bore for axial displacement only, a transverse pin attached to the end of said spindle proximal to said body and extending laterally through said longitudinal slots, the hub of the corresponding wohibler means being pivotable on both ends of said `transverse pin, a stop attached to said hub, and a lug having an inclined surface and xed to the shaft, whereby said stop is eammingly displaced by said lug upon axial displacement of the hub relative to said shaft by said nut.

3. In a device for spreading continuous webs of fabric, the combination comprising a shaft; a cylindrical `body substantially coaxially journaled on said shaft for rotation relative thereto, said body being formed with a plurality of angularly spaced longitudinally extending undercut grooves along the periphery thereof; respective wobbler means disposed on said shaft at each extremity of said body, said wobbler means each including an annular hub surrounding and pivotally secured to said shaft for limited angular displacement about an axis transverse to the axis of said shaft and offset therefrom, and an outer annular member journaled for free rotation on said hub; elongated resilient means interconnecting the outer annular members of each of said wobbler means and having portions extending outwardly of the periphery of said body; respective bearing means interposed between said hub and said member of each of said wobbler means and lbetween said shaft and said body; pack- -ing means sealing each of said bearing means against the penetration of moisture thereinto; and control means respectively assigned to each of said wobbler means for angularly pivoting said hubs from an inoperative position of said hubs perpendicular to said shaft into an operative position wherein the peripheral portions of said hubs remotest from their respective pivotal axes are inclined toward each other.

4. In a device for spreading continuous webs of fabric, the combination comprising a shaft; a cylindrical body substantially coaxially journaled on said shaft for rotation relative thereto, said body being formed with a plurality of angularly spaced longitudinally extending grooves along the periphery thereof; respective wobbler means disposed on said shaft at each extremity of said body, said wobbler means each including an annular hub surrounding and pivotally secured to said shaft for limited angular displacement about an axis transverse to the axis of said shaft and offset therefrom, and an outer annular member journaled for free rotation on said hub; elongated resilient means interconnecting the outer annular members of each of said wobbler means and having portions extending outwardly of the periphery of said body; and control means respectively assigned to each of said wobbler means and including coacting cam means on said shaft and on a respective hub for angu'larly pivoting said hubs from an inoperative position of said hubs perpendicular to said shaft into an operative position wherein the peripheral portions of said hubs remotest from their respective pivotal axes are inclined toward each other.

5. In a device for spreading continuous Webs of fabric, the combination comprising a shaft; a cylindrical body substantially coaxially journaled on said shaft for rotation relative thereto, said body being formed with a plurality of angularly spaced longitudinally extending undercut grooves along the periphery thereof; respective wobbler means disposed on said shaft at each extremity of said body, said wobbler means each including an annular hub surrounding and pivotally secured to said shaft for limited angular displacement about an axis transverse to the axis of said shaft and offset therefrom, and an outer annular member journaled for free rotation on said hub; elongated resilient means interconnecting the outer annular members of each of said wobbler means and having portions extending outwardly of the periphery of said body; respective bearing means interposed between said hub and said member of each of said wobbler means and between said shaft and said body; packing means sealing each of said bearing means against the penetration of moisture thereinto; and control means respectively assigned to each of said wobbler means and including coacting cam means on a respective hub and on said shaft for angularly pivoting said hubs from an inoperative position of said hubs perpendicular to said shaft into an operative position wherein the peripheral portions of said hubs remotest from their respective pivotal axes are inclined toward each other.

6. In a device for spreading continuous webs of fabric, the combination comprising a shaft; a cylindrical body substantially coaxially journaled on said shaft for rotation relative thereto, said body being formed with a plurality of angularly spaced longitudinally extending undercut grooves along the periphery thereof; respective wobbler means disposed on said shaft at each extremity of said body, said wobbler means each including an annular hub surrounding and pivotally secured to said shaft for limited angular displacement about an axis transverse to the axis of said shaft and offset therefrom by a distance of the order of several millimeters, and an outer annular member journaled for free rotation on said hub; elongated resilient means interconnecting the outer annular members of each of said wobbler means and having portions extending outwardly of the periphery of said body; respective bearing means interposed between said hub and said member of each of said wobbler means and between said shaft and said body; packing means sealing each of said bearing means against the penetration of moisture thereinto; and control means respectively assigned to each of said wobbler means for angularly pivoting said hubs from an inoperative position of said hubs perpendicular to said shaft into an operative position wherein the peripheral portions of said hubs remotest from their respective pivotal axes are inclined toward each other, each of said control means including a spindle nut provided with a self-locking internal thread rotatably mounted on one end of said shaft adjacent the corresponding wobbler means, said shaft having a longitudinal bore and a pair of opposed longitudinal slots communicating with said bore, a spindle having a complementary externally threaded end in engagement with said nut mounted in said longitudinal bore for axial displacement only, a transverse pin attached to the end of said spindle proximal to said 'body and extending laterally through said longitudinal slots, the hub of the corresponding wobbler means being pivotable on both ends of said transverse pin, a stop attached to said hub, and a lug having an inclined surface and xed to the shaft, whereby said stop is cammingly displaced by said lug upon axial displacement of the hub relative to said shaft by said nut.

References Cited in the file of this patent FOREIGN PATENTS 1,064,839 France Dec. 30, 1953 944,280 Germany lune 28, 1956 20,280 Great Britain of 1890 

